I have a list of equipment.
Hi Jose Fidalgo
you will need a multi line text field on your list which you connect the repeating section to. This will then store the Xml from the repeating section. Any controls you add to the repeating section need to be unconnected fields.
have a look at this excellent explanation from Eric Harris
How does Nintex save data in Repeating section fields
nintex 2013 forms repeating section data repeating sections query xml
Retrieving data ...